Method of making well pipe



Feb. 25, 1941. AROOD 2,232,973

, METHOD OF MAKING WELL PIPE Filed April 14, 1939 lyyztwa/ Patented Fete 25, 1941. I r

UNITED ,STATES PATENT OFFICE Marne or name WELLPIPE II Ashton Rood, Bakersfield, an. I

' Application April 14, 1939, Serial No. 267,839

somms. (01. 29-151) I iIhls invention relates to vwell drilling equipwell pipe of the character mentioned in which mentand relates more particularly? to pipe or the wear resisting [sheaths may be integral tubing for use in wellsand to methodsof makparts'of uniform texture and character to offer I ing the same. A general object of this invenuniform resistance to wear throughout the cirtion is .to provide a.- strong, long-wearing well cumierence of the upset portions. 5 pipe and improved methods of constructing such Another object or this invention is, to pro- P D I vide well pipe of the character mentioned in- Oil wells and gas wells are being drilled to which the wear resisting sleeves and sheaths very great depths making it necessary to emare applied in such a manner that they do not Inf ploy heavier and stronger drilling equipment. disturb, injure, or weaken the granularstruc- I For example, in the rotaryv method of drilling ture or molecular structure of the metal of the the drill pipe, to which the drilling tool is atpipe. I tached, has been strengthened by upsetting the Another object of this invention is to provide threaded end portions of the pipe sections to proexternally upset well pipe of the charoctiu'e- II vide increased wall thickness at these points. ferred to that is simple and inexpensive and The upset Joints of this type of drill pipe have that is strong and durable. I 1 a very high efliciency of strength and depend;- Ano'ther object of this invention is to provide ably withstand the stresses to which they are .a method for manufacturing upset well pipe in subjected. There are two general types of upset which hard wear-resisting sheaths are provided drill pipe, namely, the internal upset pipe and on the upset pipe portions at the timeol their 20 the external upset pipe. The internal upset pipe formationa has its fluid passage restricted at each joint and Another object of this invention is to provide these restrictions interfere with the fluid flow a method for making upset well pipe in which I and prevent the operation of certain tools in the metal of thepipe body is bonded, welded, at the drilling string. For this reason the external or 'ilxed to the wear resisting tubular sheaths g5 upset drill pipe is superior to the. internal upset when the pipe is upset and when its metal is in a pipe and has gone into extensive use. It has h ate subst n y Plastic Statebeen found, however, that the upset portions of Another object of this invention is to provide the drill pipe wear extensively through their ena method of the character mentioned in which V 80 gagement with the wall of the well during the. the forces employed to form or upset the pipe rotary drilling operation, and when the pipe is bring the metal of th p p in int at ndin moved into and out of the well. An ext rnal. contact with the metal or material of the proupset portion of the pipe usually wears u'ntective sheaths. I

evenlyand soon becomes out of round. This A further Object f s invention is to M condition sometimes causes failure through unvide a method of the character mentioned that 5 balanced stresses at the joint. Attempts have is simple and readily carried'out, and that may been made to correct this condition by heatbe performed without delaying or interfering treating the upset pipe portions andby welding "withithe upsetting op r n I on hard materials at the joints. These attempts The various objec s n f r s 0f my inhave not proven altogether successful as the vention will be fully understood from the fol- 40 methods employed to harden the upset portions lowing detailed description of typical preferred change the character and structure of the origforms of apparatus and manners of carrying out inal metal oi the pipe, setting up strains and the method of the invention, throughout which causing flaws to develop. description reference is made to the accompany- Another object of this invention is to provide ing drawing, in which:

externally upset well pipe such as drill pipe or Fig. 1 is a side elevation of a length or seewell tubing that is eflectively protected against tion of well pipe or the present invention with wear at the upset enlargements. an end portion broken away to appear in longi- Another object of this invention is to provide tudinal cross section. Figs-2 and 3 are diagramexternally upset well pipe embodying hard matic views illustrating the successive steps in 50 abrasion resisting and wear resisting sheaths one manner'of carrying out the method of the dependably bonded directly to the metal of the invention, and Figs. 4 and 5 are similar diaupset pipe portions to fully protect the same grammatic views illustrating successive steps in against wear. another manner of performing the method. ll Another object of this invention is to provide In Fig. 1 01 the drawing 1 have illustrated a u length of pipe that may be considered drill pipe of the character employed in the rotary method of well drilling, that is,- the length of pipe illustrated may be taken as a section of a rotary well drilling string. It is to be understood that the pipe may have other uses in a well. For example, it may be employed as a section of a string of well tubing, or the like. I will proceed with a detailed description of the typical length of pipe of theinventlon illustrated in Fig. 1 and will follow such description with a disclosure of the methods of the invention.

The well pipe or drill pipe of the invention may be said to comprise a pipe body I0, upset end portions II on the body I0, and wear resisting sleeves or sheaths I2 on the upset portions II.

- The body ID of the pipe may be of typical construction and design, that is, it may be a simple,

elongate tubular element. The pipe may be of seamless construction, that is, it may be formed by piercing a solid billet or it may be of lap weld or butt weld construction. The fluid pasmetal of the pipe or the sheaths I2 may have sage I3 extends longitudinally through the pipe section from one end to the other and is preferably of uniform diameter. The pipe body I0 is preferably formed of steel, for example, it may be formed of Bessemer steel or open hearth process steel.

The upset end portions II are provided on the body I0 to give the pipe body increased strength and wall thickness at its points of connection with the other elements of the well string or drilling string and to strengthen the pipe assembly adjacent. these points. The pipe section of the invention may have an upset portion II at one end only or may have upset portions II at its opposite ends, as illustrated. The upset portions II' are, of course, integral parts of the pipe body Ill and are formed of the same material or steel as the body.

The portions II are in the natureof cylindrical external enlargements of the pipe body I0. Where the pipe body III has two upset portions Il they may be of the same diameter and of substantially the same length. The inner ends I4 of the upset portions I I are beveled or tapered to merge with the external surface of the pipe bodyIfl. The end portions or the upset portions II of the pipe section are provided with threads for mating with threads of the other parts of the well string. Either one or both of the upset end portions I I may be provided with an external thread or either one or both of the portions II may be provided with an .intemal thread, as conditions may require. In the case illustrated 'one upset portion II has an internal thread I5 and the other end portion II carries an external thread I6. The first mentioned upset portion II has a tapered socket whose wall carries the internal thread I5 while the other upset portion II is provided with a longitudinally projecting pin II which carries the external thread I6. present invention is not primarily concerned with the construction, arrangement or formation of the connecting threads'IS and IS.,

The protective sleeves or. sheaths I2 are irn-' portant features of the invention. The sheaths I 2 are provided to protect the upset pipe portions II against wear through contact with the wall of the well when the well string is rotated during the drilling operations and when the pipe is run into and out of the well. In the preferred construction the sheaths I2 protect or surround substantially the entire surface parts of the upset quire.

The

sisting and wear resisting material, for example,

they may be formed of materials alloyed or compounded for this use. The tubular protective sheaths I2 may extend from adjacent the outer ends of the upset portions I I to the reduced body III of the pipe section. There may be exposed or uncovered surfaces I8 of short length at the outer extremities of the upset portions II.

It is a feature of the inventionthat the sheaths I2 are permanently bonded with the metal of the upset portions II. The sheaths I2 are incorporated in the pipe sections at the time of formation of the upset portions II and the plastic heated metal of the pipe is expanded against and intimately bonded with the metal of the sheaths I2. The internal surfaces of the sheaths pluralities of perforations I9 into which the metal of the portions II is pressed or made to flow to prdvide positive interlocking connections with the sheaths I2. The sheaths I2 are applied to or embodied in the upset portions II without changing the granular structure or the character of the pipe metal and without resorting to acetylene welding or electric welding which subjects the metal to excessive temperatures and without resorting to heat treatment processes which change the character of the metal. The wall thickness of the protective sheaths I2 may be varied as conditions may re- Where the sheaths I2 are formed of hard, long, wearing material the sheaths may have thin walls to reduce the wall thickness of the-upset portions II to a minimum degree. The sheaths I2 are embedded in the upset portions II' and may have smooth cylindrical external surfaces so that they do not present edges, shoulders, or other projections on the pipe.

- It is believed that the utility and the features of the well pipe of the invention will be readily apparent from the foregoing detailed description. The sheaths I2 fully and effectively protect the upset pipe portions I I against wear through con-.

tact with the wall of the well and through contact with the well casing and other objects. The sheaths I2 may cover the tapered end parts It and may extend to or adjacent the outer extremitiesof the portions II and thus offer complete protection for the upset portions. As above described, the sheaths I2 may be continuous and tubular and of uniform construction, to offer uniform protection for the upset portions I I. Thus the sheaths I2 prevent uneven wearing of the upset pipe portions and eliminate the posmanent parts of the pipe structure. The sheaths drawing, may be said to comprise the arrangement of a pre-heated sheath I2 in a forming bowl or die D, the arrangement of theend portion of a pipe body III .in the die D when heated to plasticity or to a temperature suitable for upsetting and the upsetting of the heated end portion of the pipe body to effect expansion of the sheath l2 and shaping of the pipe portion II and the sheath 12 into conformance to the die D.

In the method'shown in Figs. 2 and 3 the sheath 12 is pre-formed to be of approximately its final length, but to be smaller in diameter than the opening or socket S of the die D. In practice the sheath 12 as initially formed may be of just suf-' ficient diameter to receive or surround the pipe body ID with slight clearance. As illustrated the sheath 12 may be provided with the above described perforations I9. The pre-formed sheath i2 is heated prior to or following its introduction to the die D and its temperatureis such that it may be expanded to its final size without fracture or strain. The temperature to which the sheath I2 is heated of course depends upon the character of the metal of which it is formed.

The pre-formed and .pre-heate'd sheath i2 is positioned in the socket S to have its inner end engage against the tapered inner or bottom wall of the socket.

,The pipe body I0 may be introduced into the die D before, simultaneously with, or following the arrangement of the sheath I! in the die. Thepipe body Iii-is located and held to have its upset portion H of the required length when the upsetting operation is completed. The pipe body III orat least the end portion of the body Ill is heated to be readily formed or upset.- In other words; the end portion of the pipe body Ill is heated to be substantially plastic and capable .of easy deformation. 1 p

The upsetting of the pipe may be performed by a suitable mandrel M introduced int the end portion of the pipe located in the die D as described above. The mandrel M is proportioned to ive the pipe its desired internal diameter and has .an inwardly facing annular shoulder 20 engageable against the end of the' heated pipe P. The outer portion 2| of the mandrel M is proportioned to slidably operate in the socket S and when the mandrel M is moved inwardly relative to the die D the heated substantially plastic and part of the pipe body is upset to conform to the wall of the socket S in the manner well known to those skilled in the art. The heated compressed metal of the pipe flows or spreads outwardly to expand the preheated sheath i2 and to bond, fuse or weld with the metal of the sheath. The metal of the pipe flows into, andoccupies the perforations I! to lock the sheaths II to the upset portion ll. conformance to'the wall of the socket S and the pipe portion H is given its shape by the upsetting operation.

It will be observed that the upsetting of the end portion ll of the pipe results in the direct embedding of the wear resisting sheath ii in the peripheral part of the upset .pipe portion II. The application of the sheath 1! to the upset portion II is accomplished during the formation of the portion H and does not necessitate subsequent heating or working of the metal which might result in a change in its texture and the development of stresses, etc. Following the above described operations the pipe may be machined and the threads cut in the usual manner.

. to bond with the sheath The sheath I2 is expanded and shaped into comprise, generally, the arrangement of a preheated and pro-shaped sheath 1'! in the die D, the arrangement of the heated pipe body "I in the die D, and the upsetting of the heated pipe l2 and to assume the required shape.

In carrying out the method illustrated in Figs. 4 and 5 of the drawing the sheath I2 may be pre-formed to its final shape and to rather accurately fltthe socket S of the die D. In this case the sheath I! has a tapered endportion 23" adapted to seat against the tapered bottom wall of the socket S. In addition to the perforations l9 described above the sheath I2 may have internal grooves, ribs or knurling 24 to assure the dependable, permanent bonding of the pipe metal with the sheath. The sheath 12' is least the end portion to be worked upon, is

heated to the reguired temperature for the upsetting operation and this is preferably done before the pipe is introduced to the die D. The upsetting of the pipe may be performed by the mandrel M, as described above, to provide the" pipe with its upset end portion II. The metal of the upset end portion II is forcedoutwardly into firm positive contact with the roughened.

or knurled interior of the sheath l2 and the compression of the metal against the sheath assures the proper shaping of the: sheath to the wall of the die socket S. In this manner of performing the method there is no danger of excessively stressing 6r straining the sheath l2 and the sheath may be constructed of a hard material unsuited for use in the previouslydescribed method. Following the upsetting operation the pipe is removed from the die D and is machined to have the threads, etc.

. Itis to be particularly noted that the method of the invention carried outin the manners described above, provides for the application of the protective sheaths l2 to the upset portions ll without in any way changing the character of the metal of the pipe or the character of the metal of sheaths l2 permanently bonds with the sheaths and the sheaths are, in effect. embedded in the original metal of the pipe.

Having described only typical preferred forms and applications of my invention and manners of carrying out the method, I do not wish to be limited or restricted to the specific'details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within following claims:

Having described my invention, I claim:

1. The method of applying a tubular wear reQ sistant sheath to a well pipe comprising forming the sheath to have an internal diarr er greater than the initial external diameter of a pipe and to have a roughened internal surface, heating the sheath, placing the heated sheath in a die which conforms to the exterior of the sheath, heating an end portion of. the pipe to plasticize the same, insetting said heated end portion of the pipe in the die to be within the heated sheath, subiectingsaid the scope of the initial external diameter of the pipe, heating the sheath, inserting the sheath in a die shaped to conform to the exterior of the sheath, heating an end portion of the pipe to render the same plastic, inserting the heated end portion of the pipe into said die to be received in the heated sheath, increasing the wall'thickness of said end portion of the pipe to cause the metal thereof to flow into the perforations ofthe sheath and to conform to and bond with the internal surface of the sheath by externally upsetting said end portion of the pipe while within the sheath and r sheath thereon from the die.

die, and then removing the pipe with the sheath thereon from the die.

3. In the manufacture and forming of a length of drill pipe, forming a wear taking sheath having a portion with .a rough internal surface and 5 an internal diameter materially greater than the external diameter of the pipe, heating the sheath, placing the heated sheath in a die which substantially conforms to. the exterior of the sheath,

heating an end portion of the pipe to render it 10 plastic or readily formable, inserting the heated end portion of the pipe in the die to assume a position within the heated sheath, upsetting said heated end portion of the pipe by subjecting it to longitudinal compression forces to cause the said portion of the pipe to conform to and securely bond with the rough internal surface of the sheath, and then removing the pipe with the 20 ASHTON ROOD. 

